Ayotzinapa Fact Sheet: Investigating the Enforced Disappearance of 43 Students in Mexico

What happened the night the students disappeared?

On September 26, 2014, a group of students studying to be teachers at a rural college (known in Mexico as a “normal”) in Ayotzinapa, Guerrero (Escuela Normal Rural Raúl Isidro Burgos) commandeered commercial passenger buses in the nearby city of Iguala, Guerrero. The students intended to use the buses to travel to Mexico City to participate in a march to commemorate a 1968 student massacre. Commandeering passenger buses is a traditional practice of students from the rural colleges, or “normales,” throughout Mexico; the practice is common, widely recognized, and largely tolerated. In previous incidents authorities in Guerrero had taken action to prevent students from taking buses, but the practice had never been met with lethal force or sustained pursuit.

The students left Ayotzinapa traveling in two buses that they had previously commandeered. They had no intention of going to Iguala, and went only because the driver of another bus they were attempting to commandeer at a toll booth outside of the city said he had to drop off his passengers at the Iguala bus station. At the Iguala station, the students decided to commandeer three buses. In total, the students used five buses that evening. After leaving the Iguala station, the students started heading for the highway in order to return to Ayotzinapa. They took different routes when leaving the bus station and were therefore traveling in three separate groups: one group of students contained three buses; the other two buses were traveling alone.

In a series of coordinated attacks that took place over the course of three hours, all three groups of students were pursued and intercepted by security forces in the area. The attacks were carried out primarily by municipal police from Iguala and the neighboring city of Cocula, at times with the participation of Federal Police, state police, and investigative police, and with the knowledge of the army. Authorities continued to use lethal force even after the buses were stopped and the students were offloaded. As a result of the attacks, six people were killed and over 40 people were injured, some gravely. Among the victims were students, passersby, members of a youth soccer team, and teachers and other individuals that came to the students’ aid. During the attacks, municipal police detained 43 of the students who have not been seen since. The active participation of state authorities in the students’ disappearance deems it an “enforced disappearance.”

To date, the fate of only one of the 43 students has been confirmed. In December 2014, through DNA testing, a specialized lab at the University of Innsbruck in Austria identified a sample of remains that belong to Alexander Mora Venancio.

What is the Group of Experts?

Following the attacks on the students, the Mexican government, the victims’ families and their legal representatives requested technical assistance from the Inter-American Commission on Human Rights in the investigation of the case. In November 2014, the three parties signed an agreement that formed an Interdisciplinary Group of Independent Experts (Grupo Interdisciplinario de Expertos Independientes), whose official mandate was to work with Mexican authorities to: search for the disappeared students, develop lines of investigation, provide attention to the victims, and address the broader problem of enforced disappearances in Mexico. The Group of Experts is made up of five individuals: Carlos Martín Beristain (Spain), Angela Buitrago (Colombia), Francisco Cox Vial (Chile), Claudia Paz y Paz (Guatemala), and Alejandro Valencia Villa (Colombia), all of whom are internationally recognized for their exemplary work in the areas of criminal investigations, human rights, and attention to victims.

The Group of Experts began working in March 2015 and had an initial mandate of six months with the possibility of extension. In October 2015, the Mexican government agreed to renew the Experts’ mandate for an additional six months. The Group of Experts’ mandate will expire at the end of April 2016.

Who are the Argentine forensic experts working on the case?

The Argentine Forensic Anthropology Team (Equipo Argentino de Antropología Forense, EAAF) is a nongovernmental, independent team established in the 1980s that provides forensic services in cases of human rights violations worldwide. The EAAF has a history of providing forensic assistance to Mexican authorities. The EAAF worked with Mexican authorities and victims’ families to identify the remains of women and girls in Ciudad Juárez and Chihuahua City after a wave of female homicides in the 1990s and 2000s. Currently the EAAF is working with Mexican organizations and the government on the forensic commission tasked with identifying migrant remains found in mass graves in San Fernando, Tamaulipas and Cadereyta, Nuevo Leon.

At the request of the victims’ families and their legal representatives, and with the Mexican government’s agreement, the EAAF began working on the investigation of the 43 disappeared students in early October 2014, about a week after the students were forcibly disappeared.

What has the Group of Experts found?

One of the most important contributions of the Group of Experts’ work on the case has been to scientifically disprove the Mexican government’s original theory that after their detention by municipal police, the 43 disappeared students were handed over to members of the criminal group Guerreros Unidos who killed them and burned their remains in a trash dump in Cocula. This scientific analysis was included in its preliminary report made public on September 6, 2015, in which the Group of Experts also proposed new lines of investigation for the case. Below is a summary of the main findings of this report.

The students were not burned at the trash dump. The Group of Experts hired an internationally recognized fire specialist to examine the Cocula trash dump where the students were allegedly murdered and burned. This analysis did not uncover any evidence of a fire large enough to cremate 43 bodies, nor evidence that sufficient materials were available to fuel a fire long enough and large enough to burn the bodies. A fire of such dimensions would have set fire to the vegetation surrounding the trash site. Satellite images from the night of the students’ disappearance provided to the Experts by the Mexican government do not show evidence of a fire in the trash dump the night the Mexican government claims the students were killed and incinerated, nor anywhere near this area. Additionally, a meteorological study revealed moderate
rainfall in the area on the night of the students’ disappearance.

The motive for the attacks may be related to drug trafficking.The Mexican government originally concluded that authorities attacked the students in order to prevent them from protesting a local political event in Iguala; however the Group of Experts found that bythe time the students arrived in Iguala, the event was already over. The Experts concluded that a possible motive for the massive and sustained attack against the students was their unintentional intervention in an operation of the Guerreros Unidos drug trafficking organization, which uses passenger buses to smuggle drugs to the United States. The state of Guerrero is a large producer of poppy and Iguala is an important hub for the northbound trafficking of heroin, specifically to Chicago, Illinois. Given the high level of coordination of the local police forces in the attacks, the extreme violence used against the students, and the focus on preventing the buses from leaving the city, the Experts consider that a logical motive for the attack may be that the students unintentionally commandeered a bus containing heroin or bulk cash and recommend that this hypothesis be investigated further.

All of the security forces in the area were aware of the attacks but did not intervene to protect the students.Through the use of a communication system, called C-4, the Federal Police, state police, municipal police, and military officials in and around Iguala were aware of the multiple attacks against the students yet did not come to their aid. Recordings from the C-4 communications show that, prior to the attacks, security officers knew of the students’ intentions to commandeer buses and had monitored their movements even before they arrived in Iguala. There are also reports of the presence of security forces at the crime scenes during various points in the night. For example, testimonies point to federal and investigative police being present where one of the buses was attacked by municipal police; a military intelligence agent also arrived shortly after this bus had been stopped; all of the students who were in this bus are disappeared. Additionally, the Experts conclude that the operation against the students had to have been centrally coordinated, given its sustained nature and the involvement of several patrols and two different municipal police forces (from Iguala and Cocula).

What has the EAAF found?

On February 9, 2015, after conducting its own forensic analysis of the Cocula trash dump, the EAAF concluded that there is no scientific evidence to support the theory that the students had been killed and burned at the site. The EAAF’s findings and the Group of Experts’ findings constitute two outside reports that did not find a scientific basis for the Mexican government’s theory about the trash dump. The EAAF’s main findings are:

Through satellite imagery and soil samples, the EAAF concluded that multiple, smaller-scale fires have occurred at the trash dump since at least 2010; however, there is no evidence of a fire large enough to incinerate 43 bodies.

Only one plant sample collected showed minimal signs of fire damage and the remaining samples showed no signs of fire damage. Similarly, tree stumps analyzed at the location where the Mexican government claims the students were burned showed little to no signs of fire damage.

The EAAF recovered thousands of small bone fragments at the trash dump, belonging to at least 19 individuals, that had endured severe fire damage; however there is no evidence linking these remains to the 43 students. Rather, the EAAF concludes that the trash dump had been the site of previous incinerations of human remains over time.

The bullets and casings recovered at the trash dump do not correspond to the firearms that the alleged perpetrators from Guerreros Unidos claim to have used to kill the students. Testimonies given by the alleged perpetrators specifically mention the use of hand pistols (.9mm and .38 super) and the use of one AK-47-type rifle to kill the students. However, 87% of the bullets and casings recovered at the scene do not correspond to the weapons mentioned in the testimony; only 16 casings correspond to the weapons specified. Additionally, the casings were not recovered at the location where the alleged perpetrators said they shot the students.

Furthermore, the EAAF highlights two serious concerns that call into question the Mexican government’s handling of evidence and protection of a scene under criminal investigation.

Between at least November 7 and 28, 2014, the trash dump was left completely unguarded and open to public entry. Photos circulated on the Internet show members of the general public at the trash dump during this time. This is concerning as evidence could have been harmed or manipulated.

On November 15, 2014, investigators from Mexico’s Attorney General’s Office conducted an inspection of the trash dump without notifying the EAAF. During this inspection, the government investigators recovered 42 bullet casings that were found grouped together in conditions that suggest that the casings were deliberately placed in a specific location. The EAAF also states that the casings were found in an area of the trash dump that had already been inspected by the EAAF and government investigators prior to the November 15 discovery.

What actions are needed in order to advance the investigation?

Investigate the missing fifth bus and the use of buses to traffic drugs. The Experts found that only four of the five buses the students used on the night of their attack were included in the federal government’s original investigation. On the night of the attack, federal police intercepted this fifth bus, offloaded the students, and escorted the bus away from Iguala. The federal government had omitted this bus from its investigation despite testimony from the students regarding its existence, its inclusion in the initial investigation handled by Guerrero state authorities, and video footage of the bus. The fifth bus seen on video surveillance cameras during the night of the attack and described by the students does not match the bus that authorities later presented to the Group of Experts to examine. The Group of Experts hypothesizes that this missing fifth bus could have contained hidden drugs or money belonging to the Guerreros Unidos criminal organization.

Currently, the United States Department of Justice has a case concerning eight defendants charged with distributing heroin in the Chicago-area on behalf of the Guerreros Unidos. The defendants used commercial passenger buses to conceal and transport drugs from Mexico to Chicago, Illinois. Through the Mutual Legal Assistance Treaty (MLAT) that Mexico has with the United States, Mexico’s Attorney General’s Office is able to request that the Department of Justice share information about the Chicago investigation and incorporate it in the investigation of the students’ disappearance. The Group of Experts had strongly recommended that Mexico’s Attorney General’s Office submit the MLAT request and this was finally done on February 15, 2016.

The Chicago case could provide insight into how the Guerreros Unidos trafficked heroin from Iguala to Chicago, the bus companies they used, and the owners of said companies. Additionally, as part of the Chicago case investigations, U.S. authorities obtained court-authorized interceptions of the communications from various cell phones and Blackberry devices used by several individuals associated with the Guerreros Unidos, including the alleged leader of the Guerreros Unidos’ Chicago cell. The attacks against the students and their disappearance occurred in the evening of September 26, 2014 and the early morning of September 27, 2014; U.S. authorities were intercepting communications during these dates. Information provided through the MLAT will reveal to Mexican authorities whether these intercepted communications contain information related to the students’ disappearance.

Maintain one sole investigation regarding the students’ disappearance.In a February 2016 report on their activities, the Group of Experts expressed concerns about the fragmentation of parts of the investigation into the students’ disappearance. Although the case has been officially transferred to the prosecutor’s office for human rights, the office responsible for investigating cases of organized crime continues to open separate investigations that are relevant to the case. For example, suspects believed to have been involved with the students’ disappearance were recently detained, but they were charged with other crimes, such as drug possession or the illegal possession of weapons. Because these investigations are separate from the students’ case, the Experts have not had full access to them and they are unable to assess whether information in these investigations could be relevant to the students’ disappearance.

Moreover, parts of these detainees’ testimonies that support the trash dump theory have been leaked to the media, but the information provided in the leaked testimonies has not been corroborated. The Group of Experts has requested that the Mexican Attorney General’s Office investigate the source of the leaked information. The theory about the trash dump has been scientifically disproven by two independent expert reports. It is important that all authorities within the government fully recognize this and commit to pursuing new lines of investigation.

Allow the Group of Experts to be present in interviews with the military.Mexican authorities have repeatedly denied the Group of Experts’ access to the soldiers based in Iguala, Guerrero. The military, through the C-4 communication system, was aware of the students’ movements that evening and the multiple attacks on the students. According to testimonies, during the evening a group of soldiers entered the police station and searched the cells where some of the students were said to have been taken. A military intelligence agent was also present at the scene of one of the attacks on the students and witnessed their detention by municipal police; he reported his observations back to his superiors over the C-4 system and took photos and video on a cellular phone. These communications and evidence have yet to be provided to the Mexican authorities. The military has also not granted access to C-4 communications from two specific periods during the night of the attacks.

The Group of Experts has been able to directly interview other federal authorities, as well as state and municipal authorities, victims, witnesses, and the accused. Although soldiers have provided testimonies to Mexican officials, the Experts have a series of questions that they would like to ask soldiers and they are requesting to, at a minimum, be present when the federal prosecutors conduct these interviews with the soldiers.

Continue to search for the disappeared students.It has been scientifically proven that the students were not killed and burned in the trash dump; therefore, authorities must continue to search for the disappeared students elsewhere. The Group of Experts has proposed different areas to conduct the search and the Mexican government is examining these areas.

Investigate the obstruction of justice.Authorities involved in the original, flawed investigation of the 43 students’ disappearance should be investigated for possible obstruction of justice and cover up attempts. Medical reports by Mexico’s Attorney General’s Office show that 70% of the detainees in the case had injuries indicative of torture or mistreatment. Given that the majority of the government’s evidence to support its theory about the trash dump was based on the confessions of the detained suspects, the confirmation of torture would further undermine the credibility of the government’s original investigation and raise concerns about coerced confessions. The Wall Street Journal recently highlighted the case of one of the key detained suspects who reported he was tortured.